Question

我创建了一家Lawnchair商店并保存了它。请参阅以下代码：

var DB = new Lawnchair({ name: "DB", adapter: ["indexed-db", "webkit-sqlite", "ie-userdata", "blackberry-persistent-store", "dom", "window-name", "gears-sqlite", "memory"] });
DB.save({ key: "resKey", res: res});

这里res是一个javascript对象，它是存储的数据。

但是当我下次关闭并重新打开网页时，我想检查这个商店是否存在。如果商店存在，我想检查该文件是否存在。怎么做这些检查？

谢谢

PS - 有什么好的资源我可以学习Lawnchair吗？

Answer 1

经过大量的试验，我想出了以下内容：

// create a store //* CORRECT TO USE
DB = new Lawnchair({ name: "DB", adapter: ["indexed-db", "webkit-sqlite", "ie-userdata", "blackberry-persistent-store", "dom", "window-name", "gears-sqlite", "memory"] });
//Save a document/table
DB.save({ key: "resKey", data: res }, function () {
    //Access the created store
    DB = Lawnchair({ name: "DB", adapter: ["indexed-db", "webkit-sqlite", "ie-userdata", "gears-sqlite", "blackberry-persistent-store", "dom", "window-name", "memory"] });
    console.log(DB)
    //check if the document exists based on the key we used to create it
    DB.exists("resKey", function (e) {
        console.log("exists : " + e)
        if (e == true) {
        //get all records from the store
            DB.all(function (r) {
                console.log(r);
        //remove all document/table from the store
                DB.nuke(function () {
                    console.log("Data nuke-ed");
            //check if the document exists based on the key we used to create it
                    DB.exists("resKey", function (e) {
                        console.log("exists : " + e)
                        if (e == true) {
                //get all records from the store
                            DB.all(function (r) {
                                console.log(r);
                            });
                        } else {
                            console.log("Data deleted");
                        }
                    });
                });
            });
        } else {

        }
    });
});

请告诉我这是否是正确的方法，或者是否有更好的方法。如果你喜欢我的努力，请给我积分 :)

Lawnchair：检查商店及其文件存在

1 个答案: